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Photosynthesis

Photosynthesis (pron.: /foʊtoʊˈsɪnθəsɪs/; from the Greek φώτο- [photo-], "light," and σύνθεσις [synthesis], "putting together", "composition") is a process used by plants and other organisms to convert the light energy captured from the sun into chemical energy that can be used to fuel the organism's activities. Photosynthesis occurs in plants, algae, and many species of bacteria, but not in archaea. Photosynthetic organisms are called photoautotrophs, since they can create their own food. In plants, algae, and cyanobacteria, photosynthesis uses carbon dioxide and water, releasing oxygen as a waste product. Photosynthesis is vital for all aerobic life on Earth. In addition to maintaining normal levels of oxygen in the atmosphere, photosynthesis is the source of energy for nearly all life on earth, either directly, through primary production, or indirectly, as the ultimate source of the energy in their food,[1] the exceptions being chemoautotrophs that live in rocks or around deep sea hydrothermal vents. The average rate of energy capture by photosynthesis globally is immense, approximately 130 terawatts,[2][3][4] which is about six times larger than the power consumption of human civilization.[5] As well as energy, photosynthesis is also the source of the carbon in all the organic compounds within organisms' bodies. In all, photosynthetic organisms convert around 100–115 thousand million metric tons (i.e., 100–115 petagrams) of carbon into biomass per year.[6][7] Although photosynthesis can happen in different ways in different species, some features are always the same. For example, the process always begins when energy from light is absorbed by proteins called photosynthetic reaction centers that containchlorophylls. In plants, these proteins are held inside organelles called chloroplasts, while in bacteria they are embedded in theplasma membrane. Some of the light energy gathered by chlorophylls is stored in the form of adenosine triphosphate (ATP). The rest...

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...Photosynthesis
Light reaction of photosynthesis occurs on the thylakoid membrane inside of chloroplast. Light energy excites electrons that are carried down an electron transport chain. The purpose of this is to give the hydrogen ions the energy they need for active transport. It is active because the concentration of hydrogen ions outside the thylakoid is less than inside. Now that there is a high concentration of hydrogen inside the thylakoid, ATP synthase can occur. As the hydrogen go through the ATP synthase ATP (energy) is produced. The main difference between the C3 and C4 cycle is that carbon dioxide directly enters the Calvin cycle in C3 plants. C3 plants do better in high CO2 environments.
Photosynthesis consists of light reactions and dark reactions. Light dependent reactions are reactions taking place in the chloroplast in which the absorption of a photo leads to the formation of ATP and NADPH. Light independent reactions are the series of biochemical reactions in photosynthesis that do not require light to proceed, and ultimately produce organic molecules from carbon dioxide. This process can be simplified in this equation: 6CO2 + 12H2O+energy= C6H12O6. It means photosynthesis is a process in which carbon dioxide (CO2), water (H2O) and light energy are utilized to synthesize an energy-rich carbohydrate like glucose (C6H12O6) and to produce oxygen (O2) as a by-product. Photoautotrophs...

...The respiration and photosynthesis cycle is the process by which plants and animals interact in a codependent and symbiotic manner to produce the nutrients, gases, and energy that they require to survive. Plants obtain energy from sunlight and use it to combine carbon dioxide and water into glucose and oxygen. This process is called photosynthesis. Animals eat plants containing glucose, and combine glucose and oxygen, releasing energy, water, and carbon dioxide. This process is called respiration. Plants take in carbon dioxide produced by animals, and release oxygen which animals require. Animals take in oxygen produced by plants, and release carbon dioxide which plants require. Plants obtain energy from the sun, store that energy in glucose, and animals obtain the energy stored in glucose by eating plants. Plant photosynthesis and animal respiration are symbiotic processes which occur in a continuous and cyclical manner, making life on Earth as we know it possible.
To many students, the most perplexing aspect of photosynthesis is how plants obtain energy from sunlight. To understand how plants obtain energy from sunlight, one must understand kinetic energy. Kinetic energy is energy resulting from motion (Brown & Schwartz, 2009). Light is literally a photon, a tiny moving particle. If a photon of light hits another object it can impart energy to that object. This is similar to a game of pool in which a cue ball hits...

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Assignment 1 – PAPER #1; PHOTOSYNTHESIS AND CELLULAR RESPIRATION
Name: Melvin G. Abramson
SCI 115 – Essentials of Biology
Professor: Casey Bethel
Date: May 1st, 2012
Photosynthesis is the progression of translating light energy to chemical energy and storing it in the acquaintance of sugar. This process occurs in plants and some algae. Photosynthesis takes place in the chloroplasts, distinctively using chlorophyll, the green pigment implicated in photosynthesis. Photosynthesis mainly transpires in plant leaves. The two parts to photosynthesis are light and dark reactions. The light reaction comes about in the thylakoid membrane and then switches light energy to chemical energy. Each of these differently-colored pigments can attract a slightly different color of light and pass its energy to the central chlorophyll molecule to do photosynthesis. The energy harvested via the light reaction is stored by structuring a chemical called ATP (adenosine triphosphate), a compound employed by cells for energy storage. This molecule is very similar to the building blocks for our DNA. The dark reaction takes place in the stroma within the chloroplast, and converts CO2 to sugar. This reaction does not really require light but it do necessitate the products of the light reaction (ATP and another chemical called NADPH). The dark reaction...

...1. Explain how photosynthesis and respiration are linked in order to provide you with energy from the food you eat.
Include in your paper:
â€¢Complete descriptions of photosynthesis and aerobic respiration.
â€¢Describe how these two processes are linked between plants and animals based on the reactants and products (water, carbon dioxide, glucose and oxygen) of both pathways.
â€¢Include a description of how energy is transferred from sunlight to ATP, from ATP to sugars, and from sugars to your cells.
Photosynthesis is the process whereby plants utilize C02, H2O and Sunlight to create food in the form of a sugar called glucose. As a byproduct of this reaction, the plants also release oxygen.
Respiration is the process where cells use glucose, to release stored energy. In the process, cells release CO2.
Photosynthesis takes place in Chloroplasts which are found mostly in the plant leaves. Chloroplasts are organelles composed of a phospholipid inner and outer membrane. Between these 2 membranes is an intramembranous space. Inside the inner membrane is a fluid called the stroma which contains thylakoids, where photosynthesis takes place.
The thylakoids are shaped like pancakes and are bounded by a membrane. Photosynthesis takes place on the thylakoid membrane. The thylakoid membrane has proteins embedded in it. The pigment chlorophyll is embedded in specialized proteins...

...The term photosynthesis means “pulling apart with light” in Greek.
True__ 13. The energy of sunlight is stored in the chemical bonds of carbohydrates.
14. Complete the table comparing two types of organisms.
Autotrophs and Heterotrophs
Type
Description
Examples
Autotrophs
An organism that is able to create its own food through photosynthesis (simple organic substances)
Plants
Heterotrophs
An organism that “feeds” by absorbing complex organic substances.
Animals/humans
8.2 Photosynthesis: An Overview
Chlorophyll and Chloroplasts
For Questions 1–6, complete each statement by writing the correct word or words.
1. The chlorophyll of light determines its color.
2. Chemicals that absorb light are called pigments.
3. Chlorophyll makes plants look green because it reflects green light.
4. Chloroplasts contain an abundance of saclike photosynthetic membranes called Thylakoid.
5. The Stroma is the fluid portion of the chloroplast located outside the thylakoids.
6. The visible light absorbed by chlorophyll raises the energy level of the chlorophyll’s electrons.
7. Label the internal parts of the chloroplast below.
Stroma
Lumen Thylakoid
High-Energy Electrons
8. Where do the high-energy electrons carried by NADPH come from?
Photosystem I
An Overview of Photosynthesis
For Questions 9–11, write the letter of the correct answer on the line at the left....

...The effect of differing wavelengths of visible light on the photosynthetic activity of Beta vulgaris
Introduction
Photosynthesis is a crucial biological process that occurs within the chloroplasts of plant cells where CO2 + H2O + Sunlight C6H12O6 + O2. The chloroplasts use light, an electromagnetic energy source, to produce food for the plant in the form of sugar molecules. During photosynthesis, the excited electrons from the light pass through proteins in the electron transport chain (ETC), where ATP and NADPH are produced. The CO2 absorbed by the plant are then fixed into carbohydrates by these two organic molecules (Hoober 1984; Halliwell 1984). It is currently known that plants do not use every colour of the visible light spectrum when undergoing photosynthesis, and that the different wavelengths of light are absorbed by the chlorophyll at different rates. In green land plants, the blue and red lights are most readily absorbed by the cells, whereas green light is not easily absorbed (Roberts and Ingram 2001).
Photosynthesis is crucial to the survival of most species on the earth. It produces oxygen which is important for cellular respiration and glucose which provides the energy for living organisms in order to survive. If plants are not undergoing photosynthesis efficiently, or at all, then not enough oxygen and glucose are being produced. This can lead to detrimental effects on the entire...

...Photosynthesis
Green plants absorb light energy using chlorophyll in their leaves. They use it to react carbon dioxide with water to make a sugar called glucose. The glucose is used in respiration, or converted into starch and stored. Oxygen is produced as a by-product.
This process is called photosynthesis. Temperature, carbon dioxide concentration and light intensity are factors that can limit the rate of photosynthesis.
Photosynthesis summary
Photosynthesis [photosynthesis: The chemical change that occurs in the leaves of green plants. It uses light energy to convert carbon dioxide and water into glucose. Oxygen is produced as a by-product of photosynthesis. ] is the chemical change which happens in the leaves of green plants. It is the first step towards making food - not just for plants but ultimately every animal on the planet.
During photosynthesis:
* Light energy is absorbed by chlorophyll, a green substance found in chloroplasts in some plant cells and algae
* Absorbed light energy is used to convert carbon dioxide (from the air) and water (from the soil) into a sugar called glucose
* Oxygen is released as a by-product
This equation summarises what happens in photosynthesis:
Some glucose is used for respirationrespiration: Chemical change that takes place inside living cells, which uses glucose and oxygen to produce...